Variable position low profile shutter valves

ABSTRACT

A method of mixing air in an HVAC system includes the step of simultaneously and differentially rotating the valve plates different degrees of rotation to differentially control air flowing in the housing. An assembly for controlling air flow in an HVAC system includes a mechanism for simultaneously and differentially rotating valves different degrees of rotation. The mechanism includes a control device on each shaft of each valve including a pin extending axially from each valve plate. A slide defines a plurality of serpentine slots with one of the pins slidably disposed in each of the slots. The slots each follow a path incongruent from one another for differentially rotating the valve plates in response to the slide sliding along the guide and the pins moving along the paths of the slots.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates generally to an HVAC system. More specifically it relates to an assembly for mixing hot air and cooled air in an HVAC system.

2. Description of the Prior Art

Vehicle manufacturers are requesting HVAC modules that are smaller, lower cost, lower mass and require less time to develop. One of the components that comprise these HVAC modules is the air distribution and tempering valves. These valves which are found in production today are manufactured from metal with foam or rubber for sealing; from plastic with foam or rubber for sealing; or from fabric that is slid over a smooth plastic surface (i.e. film valve) in which air pressure pushing the fabric against the plastic surface provides the sealing. The plastic or metal valves either rotate about an axis (i.e. butterfly, end pivot) to regulate airflow through a given air passage or slide within a track (i.e. guillotine) allowing air to pass through a given air passage. While the film has take up and let-off shafts that spool and un-spool material therefore shifting apertures that are cut in the film to align with openings in the case therefore regulating airflow through a given passage.

Typically, these valves are arranged in parallel and rotate together in a 1:1 relationship. For example, the outer valves may be linked via a lever to a center valve. The center valve has a coupler for attachment to an actuator. As the actuator rotates this valve, the links transfer the motion to the outer two valves resulting in a 1:1 relationship in angular travel, i.e., all valves rotate in unison. Generally, there are two sets of valves wherein one set of valves directs cooled air exiting the evaporator and the other set of valves directs heated air exiting the heater.

Examples of such valve assemblies are disclosed in U.S. Pat. Nos. 6,254,475, and 6,814,137.

U.S. Pat. No. 6,254,475 to Danieau et al. describes an air flow control assembly including a frame carrying pivotable vanes, which are rotated on parallel axes by a common drive mechanism. The setting of the vanes is variable between a maximum flow position, in which the flaps have a minimum inclination with respect to the direction of air flow through the register, and a no-flow position in which this inclination is a maximum. The drive mechanism controls the pivoting of the vanes in such a way that they all rotate by the same degree of rotation, with adjacent vanes rotating in opposite directions.

SUMMARY OF THE INVENTION AND ADVANTAGES

The invention provides an HVAC system including a mechanism for simultaneously and differentially rotating valves plates different degrees of rotation and method of mixing air in an HVAC system including the step of simultaneously and differentially rotating the valve plates different degrees of rotation to control air flowing in the housing.

Typical valve assemblies, in which the valves rotate in 1:1 relationship to one another, do not promote mixing of the hot and cold air causing hot and cold air separations that impact linearity. The present invention avoids the hot and cold air separations by improving mixing of the hot and cold air streams while using a single input to actuate rotation of each valve plate.

BRIEF DESCRIPTION OF THE DRAWINGS

Other advantages of the present invention will be readily appreciated, as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings wherein:

FIG. 1 is a cross-sectional view of an embodiment of the invention illustrating the valve plates at different degrees of rotation;

FIG. 2 is a cross-sectional view of an embodiment of the invention illustrating the mechanism including a slide having incongruent slots;

FIG. 3 is a perspective view of the embodiment shown in FIG. 2 illustrating the warm air valve plates being in a closed position;

FIG. 4 is a perspective view of the embodiment shown in FIGS. 2 and 3 illustrating the valve plates at different degrees of rotation;

FIG. 5 is a perspective view of the embodiment shown in FIGS. 2-4 illustrating the lever arms disposed on the shafts of the valves and the teeth of the slide engaging the gear;

FIG. 6 is a perspective fragmentary view of an embodiment of a valve; and

FIG. 7 is a perspective fragmentary view of an alternative embodiment of a valve.

DETAILED DESCRIPTION OF THE INVENTION

Referring to the Figures, wherein like numerals indicate corresponding parts throughout the several views, an assembly for controlling air flow in an HVAC system is generally shown.

A housing 20 defines a passage for conveying air and a blower 22 is disposed in the housing 20 for blowing the air through the passage of the housing 20. An evaporator 24 is disposed in the housing 20 for cooling the air flowing in the passage. A heater 26 is disposed in the housing 20 for heating a portion of the air flowing in the passage. A frame 28 is generally indicated and has a first half 30 generally indicated and defining a first end 32 and a second half 34 generally indicated and defining a second end 36. The frame 28 extends transversely to the passage between the first end 32 and the second end 36 in the housing 20.

A plurality of cool air valves 38 are generally indicated and are rotatably supported on the first half 30 of the frame 28 for rotation between open and closed positions to control cooled air exiting the evaporator 24. The cool air valves 38 include parallel valve plates 40 each generally indicated and each having a shaft 42 fixed relative to the valve plate 40 and with a control device 44 generally indicated and extending through the frame 28. Similarly, a plurality of warm air valves 46 are generally indicated and are rotatably supported on the second half 34 of the frame 28 for rotation between open and closed positions to control heated air exiting the heater 26. The warm air valves 46 include like parallel valve plates 40 each generally indicated and also having a shaft 42 fixed relative to the valve plate 40 and with a like control device 44 generally indicated and extending through the frame 28. The cool air valves 38 and warm air valves 46 are best illustrated in FIG. 5.

The valve plates 40 of the valves 38, 46 may be thin, flat plates extending from the shaft 42 and having a uniform thickness as shown in FIG. 6. Alternatively, the valve plates 40 may have a thickness which is non-uniform. Specifically, the thickness of the valve plates 40 may vary wherein the thickness of each valve plate 40 is greatest at the location where the first half 30 of the frame 28 meets the second half 34 of the frame 28 and decreases outwardly, as shown in FIG. 7. In other words, a portion of the valve plate 40 located at the center of the shaft 42 has the greatest thickness and the portions of the valve plate 40 located at the perimeter of the plates have the smallest thickness. As shown in FIG. 7, the thickness of the valve plate 40 decreases as it extends radially away from the shaft 42.

The invention is distinguished by a mechanism 48 generally shown in FIGS. 2-5 for simultaneously and differentially rotating the valve plates 40 different degrees of rotation, including zero degrees, which means one or more valve plates 40 can be retained in a stationary position. Additionally, one or more valve plates 40 can be retained in a dwell, i.e., can be stationary over a specified period of time. In other words, the mechanism 48 rotates each valve plate 40 a predetermined degree of rotation which is dedicated to that valve plate 40 for a single input, i.e., each valve plate 40 rotates a predetermined degree different from all other valve plates 40 in each respective half of the frame 28.

For example, in an assembly having four valve plates 40 on each half of the frame 28, a specified input may rotate the valve plate 40 closest to the control device 44 of the shaft 42 positive a degrees from an open or axially aligned position, while the next closest valve plate 40 rotates a+x degrees, the third closest valve plate 40 rotates a+x+y degrees, and the valve plate 40 closest to a center of the shaft 42 rotates a+x+y+z degrees. Although the valve plates 40 in FIG. 5 may appear to be rotated the same degree because of the perspective, the valve plates 40 are in actuality rotated different degrees of rotation.

The preferred embodiment of the mechanism 48 is shown in FIGS. 2-5, however one skilled in the art will appreciate that many other combinations of mechanical components made be used to provide a mechanism 48 for differentially rotating the valves 38, 46. As an example, a rotary cam (not shown) could be disposed adjacent the valves 38, 46 wherein the valves 38, 46 (or a lever arm attached to the valves) slide along the respective slot, trace, groove or projection within the cam as the cam rotates. Multiple cams with gear teeth around their perimeter could all rotate simultaneously while each cam has a different set of projections thereby differentially rotating the valves 38, 46.

The preferred embodiment of the control device 44, as best illustrated in FIGS. 6-7, includes a lever arm 50 extending radially from each of the control devices 44 of the shafts 42 of the valves 38, 46. The control device 44 also includes a pin 52 extending axially from the lever arm 50 in spaced and parallel relationship to the respective shaft 42 supporting the lever arm 50.

The preferred embodiment of the mechanism 48 includes a slide 54 defining a plurality of serpentine slots 56 wherein one of the control devices 44, e.g., one of the pins 52 is slidably disposed in each of the slots 56 for rectilinearly movement adjacent the valve plates 40. The mechanism 48 further includes a guide 58 generally indicated and extending from the first end 32 of the frame 28 to the second end 36 of the frame 28 wherein the guide 58 slidably supports the slide 54.

As shown in FIG. 5, the guide 58 is a U-shaped channel 60 that defines an open side and extends between the ends 32, 36 of the frame 28. The guide 58 includes a plurality of brackets 62 partially enclosing the open side of the channel 60 for restricting movement of the slide 54 in the guide 58 to retain the slide 54 in engagement with the guide 58. To actuate the mechanism 48, the slide 54 has a plurality of teeth 64, as shown in FIG. 5. A gear 66 is generally indicated and rotatably supported on the frame 28 and includes gear teeth 68 engaging the teeth 64 of the slide 54 for moving the slide 54 rectilinearly along the guide 58 between the ends 32, 36 of the frame 28. A motor (not shown) rotates the gear 66.

The slots 56 of the slide 54 each follow a path incongruent from one another, as shown in FIG. 2, for rotating the lever arms 50 different degrees of rotation thereby differentially rotating the valve plates 40 in response to rotation of the gear 66. Preferably, the slots 56 corresponding to the warm air valves 46 follow a path opposite from, or mirror-images of, the paths following by the slots 56 corresponding to the cool air valves 38.

The mechanism 48 includes a means for maintaining at least one of said valve plates 40 stationary during rotation of remaining ones of said valve plates 40 for a dwell period. For example, in the embodiment shown in the Figures, the paths of the certain slots 56 may be arranged such that the respective valve plate 40 remains stationary for a specified angle of rotation of the input gear 66.

The invention includes a method of mixing air in an HVAC system of the type including a housing 20 defining a passage for conveying air, a plurality of parallel valve plates 40 supported in the housing 20 for rotation between open and closed positions. The method is distinguished by the step of simultaneously and differentially rotating the valve plates 40 different degrees of rotation to differentially control air flowing in the housing 20. The slide 54 is moved rectilinearly adjacent the valve plates 40 and the rectilinearly movement of the guide 58 is converted to a different degree of rotation of each respective valve plate 40.

In operation, the gear 66 is rotated a specified angle and direction which slides 54 the slide 54 along the guide 58. As the slide 54 move relative to the guide 58, the pins 52 in each slot 56 of the slide 54 move along the respective path of the slot 56. As the pins 52 move along the paths of the slots 56, the lever arms 50 on which the pins 52 are disposed rotate, thereby rotating the shafts 42 of the valves 38, 46 and the corresponding valve plates 40 fixed to the shafts 42. Because the paths of the slots 56 are incongruent from one another the pins 52 follow different paths from one another and the lever arms 50 rotate different degrees of rotation for each given input rotation of the gear 66. Accordingly, the invention is distinguished by a mechanism 48 for differentially rotating the valves 38, 46 including providing the ability to dwell any desired valves 38, 46.

While the invention has been described with reference to an exemplary embodiment, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing form the scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the essential scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiment disclosed as the best mode contemplated for carrying out this invention, but that the invention will include all embodiments falling within the scope of the appended claims. 

1. An assembly for controlling air flow in an HVAC system comprising; a housing defining a passage for conveying air, a plurality of valves supported in said housing for rotation between open and closed positions to control air flowing in said housing, said valves each including parallel valve plates each having a shaft, a mechanism for simultaneously and differentially rotating said valves plates different degrees of rotation.
 2. An assembly as set forth in claim 1 wherein said mechanism includes a means for maintaining at least one of said valve plates stationary during rotation of remaining ones of said valve plates for a dwell period.
 3. An assembly as set forth in claim 2 including a control device on each of said valves.
 4. An assembly as set forth in claim 3 wherein said control device includes a pin extending axially from each of said valve plates in spaced and parallel relationship to the respective shaft.
 5. An assembly as set forth in claim 4 wherein said mechanism includes a slide defining a plurality of slots with one of said pins slidably disposed in each of said slots.
 6. An assembly as set forth in claim 5 wherein said mechanism includes a guide supported by said housing and slidably supporting said slide.
 7. An assembly as set forth in claim 6 wherein said slots of said slide each following a path incongruent from one another for rotating said valve plates different degrees of rotation in response to sliding of said slide.
 8. An assembly as set forth in claim 7 wherein said paths of said slots are serpentine.
 9. An assembly as set forth in claim 7 wherein said shaft of said valve is rotatably supported in said housing and fixed relative to said valve plates and said control device includes a lever arm extending radially from each of shafts of said valves and wherein said pin extends axially from said lever arm and said lever arms rotate different degrees of rotation.
 10. An assembly as set forth in claim 7 wherein said guide includes a U-shaped channel defining an open side and a plurality of brackets partially enclosing said open side of said channel for restricting movement of said slide in said guide to retain said slide in sliding engagement with said guide.
 11. An assembly as set forth in claim 7 wherein said slide has a plurality of teeth and further comprising a gear rotatably supported on said frame and including gear teeth engaging said teeth of said slide for moving said slide rectilinearly along said guide.
 12. An assembly as set forth in claim 7 wherein said valves include cool air valves and warm air valves.
 13. An assembly as set forth in claim 12 further comprising a frame extending between a first end and a second end transversely to said passage wherein said guide extends from said first end of said frame to said second end of said frame and wherein said frame has a first half defining said first end and a second half defining said second end and wherein said cool air valves are supported on said first half of said frame and said warm air valves are supported on said second half of said frame.
 14. An assembly as set forth in claim 13 wherein said frame has a first half defining said first end and a second half defining said second end and wherein said cool air valves are supported on said first half of said frame and said warm air valves are supported on said second half of said frame.
 15. An assembly for controlling air flow in an HVAC system comprising; a housing defining a passage for conveying air, a blower disposed in said housing for blowing the air through said passage of said housing, an evaporator disposed in said housing for cooling the air flowing in said passage, a heater disposed in said housing for heating a portion of the air flowing in said passage, a frame having a first half defining a first end and a second half defining a second end and extending transversely to said passage between said first end and said second end in said housing, a plurality of cool air valves rotatably supported on said first half of said frame for rotation between open and closed positions to control cooled air exiting said evaporator, said cool air valves including parallel valve plates each having a shaft fixed relative to said valve plate, a plurality of warm air valves rotatably supported on said second half of said frame for rotation between open and closed positions to control heated air exiting said heater, said warm air valves including parallel valve plates each having a shaft fixed relative to said valve plate, a control device disposed on each of said shafts and extending through said frame, said control device including a lever arm extending radially from each of said shafts of said valves, said control device including a pin extending axially from said lever arm in spaced and parallel relationship to the respective shaft supporting said lever arm, a mechanism for simultaneously and differentially rotating said valve plates different degrees of rotation, a means for maintaining at least one of said valve plates stationary during rotation of remaining ones of said valve plates for a dwell period, said mechanism including a slide defining a plurality of serpentine slots with one of said pins of said control device slidably disposed in each of said slots for rectilinearly movement adjacent said valve plates, said mechanism including a guide extending from said first end of said frame to said second end of said frame and slidably supporting said slide, said guide being a U-shaped channel defining an open side and extending between said ends of said frame and including a plurality of brackets partially enclosing said open side of said channel for restricting movement of said slide in said guide to retain said slide in engagement with said guide, said slide having a plurality of teeth, a gear rotatably supported on said frame and including gear teeth engaging said teeth of said slide for moving said slide rectilinearly along said guide between said ends of said frame, and said slots of said slide each following a path incongruent from one another for rotating said lever arms different degrees of rotation thereby differentially rotating said valve plates in response to rotation of said gear.
 16. An assembly for controlling air flow in an HVAC system comprising; a housing defining a passage for conveying air, a plurality of parallel valves rotatably supported in said housing for rotation between open and closed positions to control air flowing in said housing, a control device disposed on each of said valves, a slide defining a plurality of slots with one of said control devices slidably disposed in each of said slots, and a guide supported by said housing and slidably supporting said slide.
 17. An assembly as set forth in claim 16 wherein said control device includes a pin extending axially from each of said valves.
 18. An assembly as set forth in claim 17 wherein said slots of said slide each following a path incongruent from one another for rotating said shafts of said valves different degrees of rotation thereby differentially rotating said valves in response to rotation of said gear.
 19. An assembly as set forth in claim 18 wherein said slots are serpentine.
 20. An assembly as set forth in claim 19 wherein said valves include parallel valve plates each having a shaft fixed relative to said valve plate, and said pin extends axially from each of said valve plates in spaced and parallel relationship to the respective one of said shafts and wherein said control device includes a lever arm extending radially from each of said shafts of said valves and wherein said pin extends axially from said lever arm and said lever arms rotate different degrees of rotation.
 21. An assembly for as set forth in claim 18 further comprising a frame extending between a first end and a second end transversely to said passage wherein said guide extends from said first end of said frame to said second end of said frame.
 22. An assembly for as set forth in claim 21 wherein said slide has a plurality of teeth and further comprising a gear including gear teeth engaging said teeth of said slide for moving said slide rectilinearly along said guide between said ends of said frame with rotation of said gear.
 23. A method of mixing air in an HVAC system of the type including a housing defining a passage for conveying air, a plurality of parallel valves plates supported in the housing for rotation between open and closed positions, and simultaneously and differentially rotating the valve plates different degrees of rotation to differentially control air flowing in the housing.
 24. A method as set forth in claim 23 including the step of moving a slide rectilinearly adjacent the valve plates.
 25. A method as set forth in claim 24 including converting rectilinearly movement of the guide to a different degree of rotation of each respective valve plate. 